The mother of "The Sandlot" star Marty York shared her concerns online not long before she was murdered ... speaking out about the mental health of her boyfriend -- the man Marty believes killed her.
Marty's mom, Deanna Esmaeel, wrote in a schizophrenia support group on Facebook earlier this month, asking, "Anyone else here have spouse or significant other with schizophrenia .. mine doesn't trust me and accuses me of cheating constantly."
She went on to claim she's been on the receiving end of name-calling and him "becoming physical for no reason" .